Posted by Alan Bowes on October 02, 1997 at 16:59:43:
In Reply to: BRAKES GONE AGAIN! posted by JIM C. on October 01, 1997 at 21:24:48:
: I JUST FINISHED PUTTING NEW WHEEL CYLINDERS, MASTER CYLINDER, BRAKE HOSES, BRAKE LINES, AND BRAKES ON MY '41 WC- SERIES- I HAVE BEEN BLEEDING THEM FOR ABOUT A WEEK NOW AND THE BEST I CAN GET IS THE BRAKES TO JUST START GRABBING WHEN THE PEDAL IS ABOUT 1" OFF THE FLOOR- THE BRAKE SHOES ARE ADJUSTED OUT TOT THE DRUM- WHAT AM I DOING WRONG?
Are these like the M37 brakes? If so, then brake adjustment is critical. The M37 has a relatively small master cylinder bore diameter compared to the much larger wheel cylinder bore diameter. This means that a long stroke of the brake pedal is required to move the shoes only a short distance. This gives you more mechanical advantage (less braking effort), but it makes brake adjustment a critical and frequent task. The upper and lower adjustment points affect each other, so you may have to go back and forth a few times between the upper and lower adjusters before the shoe surface is close to the drum surface and equidistant from it along the whole length of the shoe. You can use the inspection port to view and measure the gap.
Generally, for the first rough adjustment, I start by adjusting the the upper AND lower adjuster cams in quite a ways to increase the gap between the shoe and the drum. Then I adjust the upper cam OUT to push the shoe firmly against the drum. Then I adjust the lower adjuster cam OUT until the shoe contacts the drum, then back it off a hair. Now I can fine-tune the adjusters with the inspection port or by feel. Again, these adjusters affect each other, so it may take a few cycles between them to get the shoes close to and equidistant from the drum.
Alan Bowes
(Salt Lake City, Utah)